The coupling blocks \(\lambda _{i,j}\)  can be viewed as Lagrange multipliers that explicitly couple the control point DoFs across a subdomain interface (\(\vec{P}_{1} \cap \vec{P}_{2}\) ) such that continuity is preserved in a weak sense [1]}. Using appropriate Schur complements to eliminate the coupled DoF contributions in each subdomain, with \(\lambda _{i,j}\)  evaluated at lagged iterates of adjacent subdomains, the set of coupled constrained equations in Equation (REF ) can be completely decoupled for each subdomain. This modified system resembles a block-Jacobi operator of the global system. The scheme illustrated in this section follows ideas similar to the Jacobi-Schwarz method [2]} and the overlapping, restricted-Additive-Schwarz (RAS) scheme [3]}.
